A chemical, commonly used in the manufacture of rubber products, may cause cancer in workers regularly exposed to it, according to research published today ahead of print in Occupational and Environmental Medicine.
The researchers from the University of Birmingham’s Institute of Occupational and Environmental Medicine found higher than expected rates of diagnosis and death from a number of cancers, amongst men working at a rubber plant in North Wales.
The study looked in particular for exposure to a chemical called 2-mercaptobenzothiazole or MBT for short, which, has been implicated in previous research as a possible carcinogen.
They looked at the death rates of 2160 employees, who had worked continuously at the plant for at least six months, between 1955-84. Of this group 363 were identified as having been exposed to MBT through work.
When the study was conducted 222 of the MBT group had died, and 136 were traced who were still alive.
Analysis of the data showed that mortality rates from cancers of the large intestine and bladder were significantly higher in workers exposed to MBT than the national average.
Less significant increases were also found for lung cancer and multiple myeloma.
Further statistical analysis of the data also showed that workers exposed to MBT were also significantly more likely to be diagnosed with bladder cancer or multiple myeloma than the 1797 workers who had never been exposed to the chemical. .
For cancer of the large intestine and multiple myeloma, there were also significant trends; the higher the exposure, the higher the elevated risk.
Dr Tom Sorahan: “Many of these workers may have exposed to MBT decades earlier, but our research shows clearly that there is a need for further research to fully understand the risks presented by MBT and if necessary to protect workers from unnecessary exposure.”
The paper: Cancer risks in chemical production workers exposed to 2-mercaptobenzothiazol is published online in the Occupational and Environmental Medicine 2009; 10.1136/oem.2008.041400]
Prof Tom Sorahan, Institute of Occupational and Environmental Medicine, University of Birmingham, Birmingham, UK